Basic uses of a camera

   Machine vision smart cameras generally consist of image acquisition units, image processing units, image processing software, network communication devices, etc. If you want to choose a suitable smart camera, you must ask 10 questions:

(1) What is important for a part positioning tool? How to evaluate its performance?

Part location tools are software tools that find parts within a vision camera's field of view. This is the first step in a typical vision application. From the simplest robot grasping operation to the most complex assembly determination task, it is often the key to judging the success of the application.

In today's production environment, part positioning poses a challenge for vision cameras. This is because changes in conditions will cause changes in the route in which the part appears in the vision camera's field of view, and the vision camera will be trained to identify the part through a reference or model of the part image. These condition changes include:

·Part rotation;

·Changes in optical measurement devices;

·Inconsistency in lighting conditions;

·Normal changes in part appearance.

(2) What role does the built-in network communication device play, and what performance should I focus on?

Network communications provide a number of important capabilities:

·It enables the vision camera to quickly transmit pass/fail result data to the PC;

·It allows vision cameras to communicate with PLCs, robots, and other automation devices;

In order to establish an enterprise-class communication connection between the vision camera and the PC, please confirm that the vision camera you are evaluating supports a wide range of network protocols, including: SMTP, FTP, DHCP, DNS, TCP/IP client server, Telnet.

In order to connect vision cameras and automation devices such as PLCs, robots, etc., please choose a vision camera that supports the following industrial protocols:

EtherNet/IP - This protocol allows vision cameras to connect to PLCs and other devices over a single Ethernet cable, eliminating the need for complex wiring configurations and expensive gateways.

·ModBus/TCP - Another network protocol that allows direct connection to other devices over Ethernet.

Ultimately, as more and more vision cameras are used in production processes, it becomes important to manage them in a centralized way. Make sure the vision camera you are evaluating allows you to manage and control vision actions over the network.

(3) Is your vision camera easy to build applications and generate user graphical interfaces?

Vision applications don't often require a hub management interface (HMI), but operators often need to make adjustments to vision cameras to make modifications as parts change, change tolerance parameters and identify part failure points.

The machine vision camera should allow you to generate a graphical user interface as you configure your system. Please confirm that the vision camera you are evaluating has this capability without requiring you to develop in VB or other high-level languages.

(4) What should you look for in reading and verifying performance?

Whether you are reading alphanumeric codes for parts on a production line, or verifying data and large amounts of coded information on medicine bottles. Characteristics to look for when evaluating read and verify performance include:

· Statistical Font Training This feature allows you to generate a model or reference image from a series of images. This allows the vision camera to better handle normal variations in print quality that it may encounter, such as low contrast, positional changes, degradation, or changes in stroke width. Unless you can be certain that every label you will print will be of high quality, this ability to develop static models will be very important to the success of your application.

·Image preprocessing tool which allows you to optimize the trained model by enhancing edge contrast and filtering out background noise in the image. The optimized model improves the reliability and repeatability of the vision camera. See question (6) for more information on image preprocessing.

·Instant image playback This allows operators and technicians to quickly and easily see fault images on the monitor. Whether the faulty image is the result of a misaligned camera or a missing label, it is important to know immediately why something went wrong and to take remedial action if necessary.

(5) How to determine the repeatability of a vision camera measurement tool?

If your application is spatial dimensional measurement, you want to make sure that your measurement tools are not only accurate, but also highly repeatable. To determine repeatability, it is best if the vision camera is fully adapted to the measuring tool. Whether you are measuring the distance between two lines or generating a circle between three points, the excellent tool set eliminates the need to programmatically define functions that are not included in the standard configuration.

(6) Does the camera have sufficient image preprocessing capabilities?

Image preprocessing tools allow users to manipulate raw images to highlight desirable features and eliminate unwanted features.

This feature is key among all vision camera features and should be included as standard. Cameras with preprocessing tools provide you with the following capabilities:

·Increase contrast between target edges and background;

·Filter out irrelevant or meaningless features in the image;

·Eliminate reflections that have been shed from the surface of the part;

·Smoothing of rough textures in images.

The accuracy and durability of vision cameras are improved with the ability to optimize raw image data.

(7) How to evaluate industrial barcode reading tools and what performance is required?

Today's vision cameras should have reliable, repeatable performance on degraded, irregular 2D barcodes, or position changes from part to part. No matter what type of marking method the part uses and what type of media surface it is marked on, they should have high performance. When choosing a vision camera based on its barcode reading characteristics, you may want to know the following questions:

·Coding quality verification capabilities look for products that can verify coding quality to establish standards. This can provide valuable information about how well the marking process is working.

·Reading rate Depending on the production line speed and production needs, you may need to verify the reading rate of a vision camera. Today's fastest vision cameras can read approximately 50 codes per second.

·Image preprocessing tool which allows you to optimize the trained model by encoding edge contrast enhancement and filtering out background noise in the image. The optimized model maximizes vision camera reliability and repeatability. Please see question (6) for image preprocessing.

·Image preprocessing tool which allows you to optimize the trained model by enhancing edge contrast and filtering out background noise in the image. The optimized model improves the reliability and repeatability of the vision camera. See question (6) for more information on image preprocessing.

·Instant image playback This allows operators and technicians to quickly and easily see fault images on the monitor. Whether the faulty image is the result of a misaligned camera or a missing label, it is important to know immediately why something went wrong and to take remedial action if necessary.

(8) Does the vision camera require a PC?

Standard vision cameras do not require a PC during configuration and production. Vision cameras should offer true plug-and-play functionality, allowing you to quickly configure your application system. Importantly, vision cameras do not require you to set up a computer at the factory. Finally, a standalone vision camera allows you to see live images from your monitor without the need for a PC.

(9) What should you know about vision camera accessories?

To ensure your system integration process is fast and efficient, choose compatible accessories from the same family as your vision camera. Sellers will test each accessory to confirm that each component can operate simultaneously without malfunction. The following is a list of attachments:

·Lighting accessories Machine vision vendors should offer a variety of lighting options because machine vision systems will be exposed to many different types of part surface properties and ambient lighting conditions. A comprehensive range of lighting modules should include ring light modules, which provide soft light even when illuminated from all directions; backlight modules, which provide maximum contrast between the part and the background; and darkfield light sources, which provide low-angle illumination for irregular parts. Imaging of surfaces.

Communication accessories ensure the provision of communication peripherals such as I/O modules and gateway modules, which enable vision cameras to quickly and easily connect to PLCs, robots, other automation devices and networks.

·Monitor Some vendors offer monitors that are compatible with the camera. When choosing a monitor, it is best to choose an LCD monitor with anti-halation protection.

·Camera housing Industrial camera housing is used to prevent dust, high temperature and rain. At the same time, it should be easy to install and suitable for many sizes and types of camera lenses.

(10) What type of technical support is provided?

When evaluating a vision camera, it is important to choose a vendor that offers a broad range of product support and training services. These services should begin with an initial application evaluation. Several important questions are:

·Is the sales representative a full-time machine vision expert?

·What is the process for application evaluation? Who is the evaluator?

·Does the vendor spend the necessary engineering resources to qualify your application, or do you pay for it yourself?

·Once selected, what kind of product support will you receive to ensure a successful installation?

·Does the selected vendor offer a variety of training options?

·Whether the selected vendor has the track record and financial stability to maintain its role as a vision solutions provider over the long term.